Transfer data as per there date in there month.

[Tiya]

I export out standing statement file from other prg. to excel. data export
like date, supply no., and o/s amt.
I want to transfer o/s amount month wise next to data as per there month
columns.
Like e.g.
First 3 columns are export.
80020 36362 56890
Date Supply No. o/s Amt Jan Feb March April Like Up to Dec
1-jan-06 A23456 45900 45900
12-jan-06 D67890 34120 34120
02-feb-06 E34679 23784 23784
17-feb-06 R4567 12578 12578
21-mar-06 N5466 56890 56890
Any help.

Thanks in advance